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Search Results: 1 - 10 of 195630 matches for " Davide D'Angelo "
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Low Energy Neutrino Measurements
Davide D'Angelo
Physics , 2012, DOI: 10.1007/s12043-012-0385-3
Abstract: Low Energy solar neutrino detection plays a fundamental role in understanding both solar astrophysics and particle physics. After introducing the open questions on both fields, we review here the major results of the last two years and expectations for the near future from Borexino, Super-Kamiokande, SNO and KamLAND experiments as well as from upcoming (SNO+) and planned (LENA) experiments. Scintillator neutrino detectors are also powerful antineutrino detectors such as those emitted by the Earth crust and mantle. First measurements of geo-neutrinos have occurred and can bring fundamental contribution in understanding the geophysics of the planet.
Seasonal modulation in the Borexino cosmic muon signal
Davide D'Angelo,for the Borexino Collaboration
Physics , 2011, DOI: 10.7529/ICRC2011/V04/0510
Abstract: Borexino is an organic liquid scintillator detector located in the underground Gran Sasso National Laboratory (Italy). It is devoted mainly to the real time spectroscopy of low energy solar neutrinos via the elastic scattering on electrons in the target mass. The data taking campaign started in 2007 and led to key measurements of 7}Be and 8B solar neutrinos as well as antineutrinos from the earth (geo-neutrinos) and from nuclear power reactors. Borexino is also a powerful tool for the study of cosmic muons that penetrate the Gran Sasso rock coverage and thereby induced signals such as neutrons and radioactive isotopes which are today of critical importance for upcoming dark matter and neutrino physics experiments. Having reached 4y of continuous data taking we analyze here the muon signal and its possible modulation. The muon flux is measured to be (3.41+-0.01)E-4/m2/s. A modulation of this signal with a yearly period is observed with an amplitude of (1.29+-0.07)% and a phase of (179+-6) d, corresponding to June 28th. Muon rate fluctuations are compared to fluctuations in the atmospheric temperature on a daily base, exploiting the most complete atmospheric data and models available. The distributions are shown to be positively correlated and the effective temperature coefficient is measured to be alpha_T = 0.93 +- 0.04. This result is in good agreement with the expectations of the kaon-inclusive model at the laboratory site and represents an improvement over previous measurements performed at the same depth.
Absence of Aquaporin-4 in Skeletal Muscle Alters Proteins Involved in Bioenergetic Pathways and Calcium Handling
Davide Basco,Grazia Paola Nicchia,Angelo D'Alessandro,Lello Zolla,Maria Svelto,Antonio Frigeri
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0019225
Abstract: Aquaporin-4 (AQP4) is a water channel expressed at the sarcolemma of fast-twitch skeletal muscle fibers, whose expression is altered in several forms of muscular dystrophies. However, little is known concerning the physiological role of AQP4 in skeletal muscle and its functional and structural interaction with skeletal muscle proteome. Using AQP4-null mice, we analyzed the effect of the absence of AQP4 on the morphology and protein composition of sarcolemma as well as on the whole skeletal muscle proteome. Immunofluorescence analysis showed that the absence of AQP4 did not perturb the expression and cellular localization of the dystrophin-glycoprotein complex proteins, aside from those belonging to the extracellular matrix, and no alteration was found in sarcolemma integrity by dye extravasation assay. With the use of a 2DE-approach (BN/SDS-PAGE), protein maps revealed that in quadriceps, out of 300 Coomassie-blue detected and matched spots, 19 proteins exhibited changed expression in AQP4?/? compared to WT mice. In particular, comparison of the protein profiles revealed 12 up- and 7 down-regulated protein spots in AQP4?/? muscle. Protein identification by MS revealed that the perturbed expression pattern belongs to proteins involved in energy metabolism (i.e. GAPDH, creatine kinase), as well as in Ca2+ handling (i.e. parvalbumin, SERCA1). Western blot analysis, performed on some significantly changed proteins, validated the 2D results. Together these findings suggest AQP4 as a novel determinant in the regulation of skeletal muscle metabolism and better define the role of this water channel in skeletal muscle physiology.
Countermeasures Assessment of Liquefaction-Induced Lateral Deformation in a Slope Ground System
Davide Forcellini,Angelo Marcello Tarantino
Journal of Engineering , 2013, DOI: 10.1155/2013/183068
Abstract: Liquefaction-induced lateral spreading may result in significant damage and disruption of functionality for structures and Slope Ground System. In this regard, finite-element simulations are increasingly providing a versatile environment in order to assess economical and effective countermeasures. Several systematic bidimensional FEM computations have been conducted to evaluate mitigation strategies under the action of an applied earthquake excitation. The presented study highlights the potential of computations in providing insights for analysis of liquefaction-induced lateral deformations. In the analysis, some specific assumptions are introduced and verified such as a nine-node quadrilateral elements, massive columns of soil with periodic boundary conditions, and a Lysmer-Kuhlemeyer dashpot used to model the finite rigidity of the underlying elastic medium. Moreover, the study aims to systematically explore the effectiveness of densification as a countermeasure and then evaluate the best extension comparing two scenarios. 1. Introduction Lateral spreading refers to the development of large horizontal ground displacements due to earthquake-induced liquefaction. This phenomenon may result in significant damage and considerable replacement costs for existing buildings and civil engineering structures (quay walls, bridge piers, etc.) since it imposes notable lateral loads and may lead to widespread failures. Such adverse response is documented during several seismic events, such as the earthquakes of Niigata, Japan (1964, [1–4]), Dagupan City, Philippines (1990, [5–8]), Chi-Chi, Kocaeli, Turkey (1999, [9]), Taiwan (1999, [10]), and recent Tohoku, Japan (2011, [11, 12]). Particularly important is the dynamic slope stability under liquefaction lateral deformation into areas where potential structures can be of interest to landslides, such as dams and river or pier banks, especially if previously predisposing phenomena have acted in the static stress field [13, 14]. In this regards, several ground remediations have been developing, such as vibroreplacement [15], solidification (cementation) [16, 17], gravel drains, or stone columns [18–21]. This paper aims to assess the seismic reliability and evaluate the ground improvement method of densification for an Italian real case study of a pier founded on a partially submerged layered ground slope strongly vulnerable to liquefaction. The earthquake response of the Ground System is simulated with a two-dimensional, advanced, nonlinear finite element model adopting the open-source computational platform OpenSees
Tollip Is a Mediator of Protein Sumoylation
Alessia Ciarrocchi, Romina D'Angelo, Chiara Cordiglieri, Ada Rispoli, Spartaco Santi, Massimo Riccio, Simona Carone, Anna Laura Mancia, Simone Paci, Elena Cipollini, Davide Ambrosetti, Marialuisa Melli
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0004404
Abstract: Tollip is an interactor of the interleukin-1 receptor involved in its activation. The endosomal turnover of ubiquitylated IL-1RI is also controlled by Tollip. Furthermore, together with Tom1, Tollip has a general role in endosomal protein traffic. This work shows that Tollip is involved in the sumoylation process. Using the yeast two-hybrid technique, we have isolated new Tollip partners including two sumoylation enzymes, SUMO-1 and the transcriptional repressor Daxx. The interactions were confirmed by GST-pull down experiments and immunoprecipitation of the co-expressed recombinants. More specifically, we show that the TIR domain of the cytoplasmic region of IL-1RI is a sumoylation target of Tollip. The sumoylated and unsumoylated RanGAP-1 protein also interacts with Tollip, suggesting a possible role in RanGAP-1 modification and nuclear-cytoplasmic protein translocation. In fact, Tollip is found in the nuclear bodies of SAOS-2/IL-1RI cells where it colocalizes with SUMO-1 and the Daxx repressor. We conclude that Tollip is involved in the control of both nuclear and cytoplasmic protein traffic, through two different and often contrasting processes: ubiquitylation and sumoylation.
RNA Sequencing of the Exercise Transcriptome in Equine Athletes
Stefano Capomaccio, Nicola Vitulo, Andrea Verini-Supplizi, Gianni Barcaccia, Alessandro Albiero, Michela D'Angelo, Davide Campagna, Giorgio Valle, Michela Felicetti, Maurizio Silvestrelli, Katia Cappelli
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0083504
Abstract: The horse is an optimal model organism for studying the genomic response to exercise-induced stress, due to its natural aptitude for athletic performance and the relative homogeneity of its genetic and environmental backgrounds. Here, we applied RNA-sequencing analysis through the use of SOLiD technology in an experimental framework centered on exercise-induced stress during endurance races in equine athletes. We monitored the transcriptional landscape by comparing gene expression levels between animals at rest and after competition. Overall, we observed a shift from coding to non-coding regions, suggesting that the stress response involves the differential expression of not annotated regions. Notably, we observed significant post-race increases of reads that correspond to repeats, especially the intergenic and intronic L1 and L2 transposable elements. We also observed increased expression of the antisense strands compared to the sense strands in intronic and regulatory regions (1 kb up- and downstream) of the genes, suggesting that antisense transcription could be one of the main mechanisms for transposon regulation in the horse under stress conditions. We identified a large number of transcripts corresponding to intergenic and intronic regions putatively associated with new transcriptional elements. Gene expression and pathway analysis allowed us to identify several biological processes and molecular functions that may be involved with exercise-induced stress. Ontology clustering reflected mechanisms that are already known to be stress activated (e.g., chemokine-type cytokines, Toll-like receptors, and kinases), as well as “nucleic acid binding” and “signal transduction activity” functions. There was also a general and transient decrease in the global rates of protein synthesis, which would be expected after strenuous global stress. In sum, our network analysis points toward the involvement of specific gene clusters in equine exercise-induced stress, including those involved in inflammation, cell signaling, and immune interactions.
Livestock Antibiotic Effects on Nitrification, Denitrification, and Microbial Community Composition in Soils  [PDF]
Sagarika Banerjee, Elisa DAngelo
Open Journal of Soil Science (OJSS) , 2013, DOI: 10.4236/ojss.2013.35024
Abstract:

The broiler (Gallus gallus domesticus) industry in the United States and several other countries routinely includes subtherapeutic levels of antibiotics such as roxarsone, virginiamycin, and bacitracin in the feed to improve bird growth yields. Large fractions of the antibiotics fed to the birds are excreted in manure (litter), which is often applied to soils to improve fertility. Some concerns with this practice are antibiotic-induced alterations in microbially-mediated nutrient cycling, which could influence plant productivity and environmental quality. To investigate this possibility, a series of lab experiments were conducted to determine the effects of increasing levels of the three livestock antibiotics on nitrification, denitrification, and microbial community composition (fatty acid methyl ester profiles) of soils collected along a catena. Roxarsone and virginiamycin significantly influenced microbial community composition and inhibited nitrification in the soils, but only at levels that were several-fold higher than expected in poultry litter-applied soils. Bacitracin did not affect microbial growth, microbial community composition, or nitrification at any concentration tested (up to 500 mg·kg-1). None of the antibiotics influenced denitrification at environmentally-relevant concentrations. Amounts of antibiotics in soil solution were greatly reduced by sorption, which followed Freundlich models in the concentration range of 1 - 500 mg·L-1. Results from this study indicated that addition of roxarsone, virginiamycin, or bacitracin to these soils at environmentally-relevant concentrations would not likely impact microbial community composition, nitrification or denitrification due to intrinsic resistance/insensitivity of microorganisms to these antibiotics and reductions in the bioavailable amounts due to sorption by soil surfaces.

The Virtuous Circle of Corporate Social Performance and Corporate Social Disclosure  [PDF]
Francesco Gangi, Eugenio DAngelo
Modern Economy (ME) , 2016, DOI: 10.4236/me.2016.712129
Abstract: Previous literature in the field of corporate social responsibility investigates whether corporate social performance can be seen as a determinant of corporate social disclosure or, conversely, if corporate social disclosure is a determinant of corporate social performance. The aim of this paper is to join these two streams of research in a unique theoretical model, which can demonstrate that there is a mutual interaction between performance and disclosure. This can result, in the long run, in a virtuous circle where higher social performance generates future higher social disclosure and this determines higher future social performance and so on. An analytical model has been adopted to demonstrate the research hypothesis. Gathering data from the portfolios of the European Socially responsible funds (SRFs) listed on the Morningstar platform in 2010, the study analyzed 160 social reports published by 80 companies during 2008 and 2009. Findings, by demonstrating the non-one-way relationship between social performance and social disclosure, confirm the existence of a mutual influence between the results gained in different CSR areas and the capability to control and communicate such performance. In this way, the paper provides not only theoretical insights, but also practical implications for managers that are required to put in place responsive and effective initiatives towards the increasing pressure exerted by the internal and external environments in which they operate.
Efficiency of a stirred chemical reaction in a closed vessel
Cristobal lopez,Davide Vergni,Angelo Vulpiani
Physics , 2002, DOI: 10.1140/epjb/e2002-00268-8
Abstract: We perform a numerical study of the reaction efficiency in a closed vessel. Starting with a little spot of product, we compute the time needed to complete the reaction in the container following an advection-reaction-diffusion process. Inside the vessel it is present a cellular velocity field that transports the reactants. If the size of the container is not very large compared with the typical length of the velocity field one has a plateau of the reaction time as a function of the strength of the velocity field, $U$. This plateau appears both in the stationary and in the time-dependent flow. A comparison of the results for the finite system with the infinite case (for which the front speed, $v_f$, gives a simple estimate of the reacting time) shows the dramatic effect of the finite size.
Superfast front propagation in reactive systems with anomalous diffusion
Rosaria Mancinelli,Davide Vergni,Angelo Vulpiani
Physics , 2002, DOI: 10.1209/epl/i2002-00251-7
Abstract: We study a reaction diffusion system where we consider a non-gaussian process instead of a standard diffusion. If the process increments follow a probability distribution with tails approaching to zero faster than a power law, the usual qualitative behaviours of the standard reaction diffusion system, i.e., exponential tails for the reacting field and a constant front speed, are recovered. On the contrary if the process has power law tails, also the reacting field shows power law tail and the front speed increases exponentially with time. The comparison with other reaction-transport systems which exhibit anomalous diffusion shows that, not only the presence of anomalous diffusion, but also the detailed mechanism, is relevant for the front propagation.
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